Formation of solid polymeric material

Abstract

A solid flexible polymeric material is formed by solidifying a water-based latex which contains an inorganic filler. The filler is sand and this may be stabilized in the latex with xanthan gum. The solid material may be a foamed or non-foamed layer which may be used as integral carpet backing, as carpet underlay, or as an adhesive for bonding a reinforcing fabric to the back of carpeting.

I claim: 
     
       1. A method of making a solid flexible polymeric material comprising the steps of: mixing a water-based latex comprising an aqueous dispersion of one or more polymeric materials selected from natural rubber, styrene-butadiene rubber, carboxylated styrene-butadiene rubber, polyvinylchloride, ethylene vinylacetate copolymer, polychloroprene, acrylic copolymers, butadiene-acrylonitrile copolymer; with   an inorganic filler comprising natural quartz sand having a graded particle size in the range 75 microns to 300 microns; and with   xanthan gum in an amount of 0.1 to 8.0 parts per 100 parts polymer by weight;   whereby a fluent mixture is obtained containing the said inorganic filler as a stable dispersion therein; and   solidifying the said mixture by setting the said latex.   
     
     
       2. A method of making a solid flexible polymeric material, comprising the steps of: (a) mixing a water-based latex comprising an aqueous dispersion of one or more polymeric materials selected from the group consisting of natural rubber, styrene-butadiene rubber, carboxylated styrene-butadiene rubber, polyvinylchloride ethylene vinylacetate copolymer, polychloroprene, acrylic copolymers and butadiene-acrylonitrile copolymer with an inorganic filler comprising natural quartz sand having a graded particle size in the range of about 75 microns to about 300 microns and with xanthan gum in an amount of about 0.1 to about 8.0 parts per 100 parts polymer by weight, whereby a fluent mixture is obtained containing the said inorganic filler as a stable dispersion therein; and   (b) applying the said mixture to a surface; and   (c) solidifying the said mixture by setting the said latex to form a layer on the said surface.   
     
     
       3. A method of forming a solid flexible polymeric material wherein a water-based latex is mixed with an inorganic filler and xanthan gum and the latex mixture is then solidified, wherein said inorganic filler comprises sand, and wherein the latex mixture is foamed. 
     
     
       4. A method according to claim 3, wherein the latex mixture is applied to a surface and solidified to form a layer thereon. 
     
     
       5. A method according to claim 4, wherein the surface comprises a surface of a reinforcing scrim whereby the layer is formed integrally therewith. 
     
     
       6. A method according to claim 4, wherein the surface comprises a back surface of carpeting material whereby the layer forms an integral flexible backing. 
     
     
       7. A method according to claim 4, wherein the surface comprises a back surface of carpeting material and the latex mixture is disposed between such surface and a reinforcing fabric whereby said layer acts to bond said fabric to said carpeting material. 
     
     
       8. A method according to claim 3 where the proportion of sand amounts to 50 to 450 parts per 100 parts polymer by weight.